An energy pyramid Name the trophic level that is always found at the base of a food chai or food web. 2. Explain what a trophic level is. Explain why there is less energy available at the top of an energy pyramid.

1. The trophic level that is always found at the base of a food chain or food web is the **producers** or **autotrophs**. These are typically plants and other photosynthetic organisms that convert sunlight into energy through the process of photosynthesis. 2. A **trophic level** refers to the position an organism occupies in a food chain or food web. It is a way to categorize organisms based on their feeding relationships and energy transfer. The main trophic levels include: - **Producers (1st trophic level)**: Organisms that produce their own food (e.g., plants). - **Primary consumers (2nd trophic level)**: Herbivores that eat producers. - **Secondary consumers (3rd trophic level)**: Carnivores that eat primary consumers. - **Tertiary consumers (4th trophic level)**: Carnivores that eat secondary consumers. - **Decomposers**: Organisms that break down dead matter and recycle nutrients back into the ecosystem. The reason there is less energy available at the top of an energy pyramid is due to the **10% rule** of energy transfer. When energy is transferred from one trophic level to the next, only about 10% of the energy is passed on to the next level. The remaining 90% is lost primarily through metabolic processes as heat, movement, growth, and reproduction. This results in a decrease in available energy as you move up the pyramid, leading to fewer organisms and less biomass at higher trophic levels.